News for hackers. Stuff that matters.

A comment on Film grain synthesis in AV1 (2019). Parent comment

Re:Film grain synthesis in AV1 (2019) by asojfdowgh on Monday July 18, 2022 @06:15PM (#32144719)
the synthesized noise only covers what is removed by the denoiser, so it all adds up to what the input is (assuming the left-in noise makes it through the encoder)
[ Parent | on HN ]
Re:Film grain synthesis in AV1 (2019) by NonNefarious on Tuesday July 19, 2022 @05:08AM (#32149198)
Do you have a citation for that? Not saying it's wrong, but I didn't see it in the article (which I admittedly skimmed pretty quickly).
[ Parent | on HN ]
Re:Film grain synthesis in AV1 (2019) by asojfdowgh on Tuesday July 19, 2022 @11:41AM (#32153183)
From the flow graph, the film grain estimation is done on the difference between the de-noised video, and the original. So it only picks up the difference that the denoiser creates.

> and estimating the film grain parameters from flat regions of the difference between the noisy and de-noised versions of the video sequence.

[ Parent | on HN ]
Re:Film grain synthesis in AV1 (2019) by NonNefarious on Thursday July 21, 2022 @02:54AM (#32176544)
OK then.
[ Parent | on HN ]